This invention relates to nose construction for high temperature furnaces, and more particularly to a suspended nose construction which provides refractory replacement from the cold side of the refractory. High temperature furnaces may include a curved wall portion known as fantail turn or nose construction which makes the transition between a vertical wall and a suspended horizontal roof, or between two walls having some other angular relationship to each other. The nose constructions to which this invention relate have their center of radius outside the cold side of the furnace.
Nose constructions have been generally made of a number of wedge-shaped refractory bricks having one set of opposing converging sides which converge toward the cold side of the nose construction, as exemplified by U.S. Pat. Nos. 1,636,603, 1,764,707, 2,132,517, 2,272,015 and 2,685,264. U.S. Pat. No. 1,582,275 discloses a hanging arch for furnaces which is constructed of wedge-shaped bricks, some arranged with their sides converging toward the cold side and some with their sides converging toward the hot side. However, it is clear that repair must be made from the inside of the furnace taught by the 1,582,275 patent and that the furnace must be shut down for such repair.
Despite advances in the art of refractory design, prolonged exposure to the extremely high temperatures to which refractories are subjected eventually wears or cracks the bricks. In order to repair the nose or replace individual bricks in the nose constructions described in the above patents, the furnace must be shut down so that workmen may remove the wedge-shaped bricks from the inside of the furnace. This is expensive and time-consuming, and would not be necessary if the individual bricks could be removed from the cold side of the furnace. The refractory bricks used in nose constructions for high temperature furnaces are generally suspended from the cold side of the furnace. The suspension systems described in the patents referred to above generally do not permit removal and replacement of bricks from the cold side of the furnace.
There is a need for a suspended nose construction for high temperature furnaces which provides for replacement of refractory bricks from the cold side of the furnace, and includes suspension means which facilitates such removal and replacement.